Selective system of telephony.



R. G. M. HASTINGS. SELECTIVE SYSTEM OF TELEPHONY. APPLICATION FILED 1110.29, 1911.

Patented May 13, 1913.

5 SHEETS-SHEET 1.

entor' Witn 1174;1 5:751

/ 1 1 V I. Attorneys- R. 0. M. HASTINGS.

SELECTIVE SYSTEM OF TELEPHONY.

APPLICATION FILED AUG. 29, 1911.

Patented May 13, 1913.

6 SHEETS-SHEET 2.

llll iltl! E K u i FE Inventor Witnesses Attorneys R. G. M. HASTINGS. A SELECTIVE SYSTEM OF TELEPHONY. APPLICATION FILED AUG. 29, 1911.

1,061,285, Patented May13,1913.

& SHEETS-SHEET 3'.

3%; ma m9 5 f? 5' Y m J ff 77 a??? Witnesses E lnv'entor I i Attorne y" R. G. M. HASTINGS.

SELECTIVE SYSTEM OF TELEPHONY. APPLIOATION TILED AUG. 29, 1911.

1,061,285. 1 Patented May 13, 1913 5 SHEETS-SHEET 4.

Witnesses E inventor v Attorneys RIG.M.HASTING&

SELECTIVE SYSTEM OF TELEPHONY,

APPLICATION FILED AUG 29 1911 B 5 h J 7 \IJ W m m m o 4 E \w E m y 0 Q A a m 7 .N\ m m {w wk M E w m Q 11 I l l I l l m Vlilll M m E 1 1 I FM w I; w I k K Yr %-M\ m M%&V

UNITED STATES Parana OFFICE,

RUBEN G. M. HASTINGS, OF COLUMBUS, OHIO, ASSIGNOR TO THE INTERNATIONATA TELEIEI-IONE C0., OF COLUMBUS, OHIO.

SELECTIVE SYSTEM OF TELEPHONY.

Specification of Letters Patent.

Patented May 13, 1913.

Application filed Augujtiujjilll Serial No. 646,697.

'uset'ul Selective System of Telephony, (Case A,) of which the following is a specification.

This invention relates to improvements in a system of telephony, and the primary object of the invention is the provision of a telephone system, employing an exchange or central station, and a series of subscribers outfits, all being connected for operation in series in what is termed a loop circuit, there being mounted in the exchange a selecting apparatus, whereby the operator when called, operates the apparatus to connect the calling subscriber to a cal-led subscriber, simultaneously lockhig out all other subscribers, and shunting their outfits, so that their transmitters and receivers are dead,

the circuits being shunted, so that such locked out subscribers cannot interfere With the parties talking, and cannot themselves call the exchange until such parties have completed their conversation and hung up the respective receivers and rung ofi at which time the selecting apparatus at the exchange is automatically operated by the removal of the jack plug, and all subscribers outfits placed again upon the line in condition for calling the exchange or being called. In systems of this character, it is generally common practice of si'ibscribers whether called'or, not, but when any neighboring subscriber has been called, to be curious and break-in on the conversation and thereby render the service unsatisfactory, for all parties concerned, the manipulation of the various receivers by the curious sub scribers causing a great loss to the companv on account of the consumption of the hattery force used in continually removing the receiver, and further requiring the employment of call bells of a great rcsistance as all .of the bells must be operaici l each time any one of the subscribers are called. this particular apparatus and system, all curious subscribers instruments are shunted or dead during the connection of the callins; and called subscribers, thus cutting out. :the battery force, and by reason of the fact "that the only bell or signal actuated is the \Vith,

one at the called subscriber-s instrument, a bell of light resistance, say 80 ohms is possible, may be employed throughout the system. But should the calling and called subscriber endeavor to monopolize. the line, the exchange operator can at any time, disconncct the jack and sever the connections bctween the called and caller, so that the other subscriber may secure service. in other words, with a system designed according to the present invention, any number of subscribers may be placed in series upon a common line, made in the form of a loop circuit, although it is to be understood that any system may be en'u loycd, the loop circuit, however, being a more econou'iicul circuit, and one which does not so readily become ineffective, in case of breaks, occasioned by storms.

.In using the present system, the calling subscriber notifies the exchange in the usual manner, that he desires comnumicul'ion with another. llhe exchange answers such subscriber, and after being given the number of the telephone with which it is desired to have communication the exchange rotates a shaft of the selecting apparatus, the indicator thereon indicating all of the various numbers a t that exchange and upon the particular loop circuit. When the exchange has manipulated the shaft to such number, the shaft is pushed upon. this action simultaneously placing the called subscriber-s instrument in direct connection with the calling subscriber, and automatically ringing his bell. and only his. the \iurious other suh scribers instruments having been shunted or caused to'bc dead with relation to the linccircuit, so even though they should endcuvor to get the exchange or listcn to the conversation, theycan neither transmit or receive, or signal the exchange. Should the *alled subscriber not answer immediately, the exchange operator without allot-ling the main selecting key, operates an auxiliary device which automatically rings the call, and this operation may be continued until the called subscriber cithcr answers or the exchange notifies the calling subscriber that the called subscriber does not answer. Upon the completion of the conversation between the calling and called subscriber, the usual ring-oil or in fact any method to notify central that the conversation is completed, is

1 jack plug and thus simultaneously releasing instrument cut or lockout herein set forth all other subscribers instruments irom their respective shunts with the-line, and permitting the use of the line to the otherswhen desired. It will thus been seen that by producing a system operating'as described, that a great annoyance t0 the conversing .sub-

scribers is dispensedwith and overcome, and

that reason of the automatic shunting of allinstrumentsbut the calling. and called subscribers that a 'great saving "to the com- .pany or system'is the resultant. 1

A still further object of this invention is the employment ofa novel form of select ing apparatus, and automatic subscribers to produce an operative system.

With theforegoing and other-objects in view whichwill appear as the description proceeds, the invention resides inthe combination and arrangement ofparts'and in the details of construction hereinafter described and .claimed, it being understood that changes in the precise embodiment of the invention herein disclosed can be made within the .scope of what is; claimed without departing-from the spirit of the invention.

In thedrawings: Figure 1 is a diagram matic view of a single subscribers set of .instruments and an exchange as employed with the present invention, a loop circuit being shown. Fig. 2 is a detail side elevation of the selecting apparatus in initial position. Fig. 3 is a similar view with the parts in the position they assume after having calleda subscriber and shunted the ones not called. Fig.4 is a detail front elevation of'the subscribers shunt mechanism in line open position. Fig. 5 is a similar view shunted, the receiver off. Fig. 6 is n. rear view-.of the subscribers shunt mechanism.

Fig. 7 is a side elevation taken from the op posite side of the selecting key-of Fig. 2;, the parts being in same initial position. Fig. '8 is a detail plan view of the hook-lock shunt disk andits pawl. Fi 9 is a vertical longitudinal sectional view through the selecting key. Fig. 10 is a top plan view of the mechanism below the selecting cylinder. Fig. ll-is a front elevation of the key with the cap removed to show the gearing and clutch. J'Fig. 12 is a section taken on line 12-19. of Fig. i). Fig.18 is a detail view of tlieselecting :key control armature.

Referring to the drawings, L and L desigpate the line conductors of a loop circuit, subscribers set, both the exchange and subscribers set being connected to the loop circuit for/the electrical transmission of intelligence. i The various detail circuits ass'hoWn in Fig. 1 will be described later on in connection with the-operation.

sockets 2, 'for the other jack the exchange or central, and S one The exchange set comprises essentially the call-up magneto M, the two plugs J, and the co-acting jack member 1, for one plug J, and the series of co-acting-calling jack lug J. The exchange visual signal device g is mounted also at the exchange, while the selecting key K, is also mounted therein, and as set forth in detail later on controls the electrical communication between two and only two subscribers sets, the onecalling asking the exchange ,to select the one called, whereby the manipulation of the selecting key K, by the exchange operator, places in telephonic communication' the calling and called subscribers, and simultaneously shunts all of the remaining subscribers,- simultaneously advising them by a visual signal that the line is busy or in use.

The subscribers set, only one here being shown, it being understood that any number, may be connected in the loop circuit, comprises essentially the receiver R and the transmitter T, a call-up and ring-0H1 magneto M, and also mounted in proper circuit the synchronously operated lock-out and shunting device'O, the detail description of which will follow later on. The device 0 "is provided with means operated automatition'of the magneto M, or the continued movementof the receiver hook annoy the parties in communication, the lock-out or shunting device operating a visual signal to indicate to the subscriber, the condition of the loop circuit, that is whether it is busy or free. .By this lock-out and shunting device, the battery B,is disconnected from the receiver and transmitter in the shunted subscribers set, so that the battery cannot be injured by the continued movement of the receiver hook, as is the'case with systems now in use. This much pertains generally to the system, but in order to fully understand the. operation of the same, the various instrumentalities that render this system possible must be considered, and each will be considered separate'ly; and then finally associated with the diagram as shown in Fig. 1, to fully set forth ,their respective uses.

Selecting 7cey.'-The selecting key, which is particularly set forth in -detail in Figs. 2,- 3, '2', 9, 10, 11,12 and 13, and'in diagram in Fig. 1, and which is mounted for operation at the exchange or central of the system, comprises "an open frame 2, and thefour cylindrical guideand supportingrods 3, 4, 5 and 6, respectively, upon which are mounted the respective parts of the key. Mounted for a reciprocatory sliding movementupon the main rod 3, is the carriage 7, havmg the central tubular portion 8, which i forms the mounting for the carriage upon 8, is a plate 9, provided with rack teeth 10,

which mesh at all times with the actuating toothed wheel 11, being upon a sleeve 11,

, said wheel being rotatably mounted upon the shaft 12, journaled transversely of the frame, between the two plates 13 and 14, which form in reality a casing. Projecting upwardly from and at each end of the tube 8, are two arms 15, which are provided with eyed terminals 16, which slidably fit upon the rod 4, and .have disposed therebetween and upon the rotatable rod 4, the selecting cylinder or drum 17, which is keyed slidably upon the rod or shaft 4, so that the said cylinder may slide upon said rod 4, and yet be caused to rotate therewith, the purpose of which will presently appear.

By carefully examining the selecting cylinder or drum 17, it will be noted that the forward portipn of the periphery thereof is provide with a series of longitudinal grooves ,'spaced apart a't'equi-distances around the cylinder, each groove represent ing one subscribers set and the exchange inthe system, there therefore being, when eleven sets are on the line, twelve grooves 18, the outer end of the shaft or rod 4, as at 19, carrying an indicator arm or pointer 20, to indicate by pointing to the numbers on the dial (not shown) the subscribers set that will be placed in communication by the proper manipulation of the key; The outer ends-of the grooves 18 terminate in the cir cumferential groove 22, which when the selecting cylinder is in' initial position, as in Fig. 2, will have the locking pin or screw 23, mounted in the frame above the cylinder, fitting therein, to prevent the movement of -the cylinder accidentally and yet permit the cylinder to be pushed inwardly to connecting position as shown in Fig. 3, through the rotation for selecting and the pushing inwardly of the operating rod 24. The rod. 24 is provided with a keyway 25, which permits the said push rod to be rotated freely to the right, butgvhcn turned to the left throws in the pawl and ratchet device 26, shown in Fig. .11. so that the shaft 24, through the gear 29, small pinion 30 and gear 31, as clearly shown in Figs. 9 and 11, will operate the rotatable rod 4, and thereby cause a simultaneous rotation of the selecting cylinder or drum 17. Upon the shaft 12 are rotatably mounted the short sleeves 11 and 11', the sleeve 11 of which carries a gear 34 and the outer large gear 34", while the sleeve 11"? carries the outer small gear 11, the intermediate large gear 33' and the inner ,small gear 33. Thus the sleeve .11 is indcpcmlcnt of the sleeve 11, and the sleeve 11' constitutes the automatic ringer controlling sleeve, while the sleeve 11" constitutes the selecting key carriage and cylinder controlling sleeve. By this arrangement when the pointer alines with any one of the dial figures, the push rod 24 is pushed inwardly, so as to slide upon the central guide rod 5, upon which is slidably mounted the main actuating racked or toothed bar 32, whose toothed portion is in mesh at all times with the gear 33.

The inward movement of the bar 32 rotates the sleeve 11", and as the call alarm actuating frame 35 is simultaneously pushed inwardly, the toothed portion or rack 34 thereof rotates the sleeve 11, through the small gear 34. The large gears 33 and 34 are a portion of a locking and releasing mechanism for the control and release of the respective racks 10, 32 and 34, the electromagnet 56and its Y-shapcd armature 51, as will presently appear, constituting the main control device for permitting the return to initial position of the racks 10,

,32 and 34 and for the retention thereof in selected positlon. At the forward end of the frame 35, are the two lugs 36 and 37, ,the lug 36 depending and in the path to be abutted by the inner end of the auxiliary puslyrod 38, while the lug 37 is to the side of the frame 35 and in the path to be actuated by the push rod 24. By this means when the push rod 24 is pushed upon, the

lug 37 is engagedamd the frame 35 is moved inwardly with the carriage of the key, but after the carriage is in selected position and is locked, the frame 35, due to the spring.44, is automatically returned to initial position, and during such return, as will presently appear, automatically causes the energization of the call up alarm 200 in the selected sub-station. 1f the selected substation requircs successive calling, the auxiliary push rod 38 is depressed, engaging the lug 36 and pushing only the frame 35,

which after having been released will be again automatically returned by the sprin 44 and ring the alarm 200 in the selected sub-station.

Journaled between the plates 13 alpd 14- and to the right of the shaft 12, as v'ewed in Figs. 2, 3, 9 and 10 is a shaft 45, having rotatable thereon the two gears 46 and 47, which are at all times in mesh with therespective large gears 33 and 34". Fast with the gear 46 is a toothed wheel 46; while fast with the gear 47 is a toothed wheel 47'. The respective pivotally mounted governor arms 48 and 49, carry the respective double detents or pawls 48' and 49, which engage their respective toothed wheels 46 and 47,

. contacts 66 due such arms and the train of gears constituting the full locking and releasing mechanism for the frames 9, 32 and 35.

As themanipulation of the carriage and selecting cylinder make the selection and line connection, it is desirable that the frame 35 be held stationary during the spring actuation or movement of the same, and

vice versa, that is that the carriage and Seis disposed to move above the governor arm 49, this action alternating, so that one governorarm is held "against movement, while the other is released. This is accomplished by the spring 57 and the electromagnet 56. Thus the energization of the electromagnet 56, will actin opposition to the spring 57 to attract the armature 54, and consequently move the terminal 52 into engagement with the governor arm 48, while the terminal 53 Will be moved from above and out of engagement with the governor arm 49.

\Vhen. the exchange operator is making a selection, and the push rod 2a has been pushed in to its full limit and released, the to the engagement thereof are closed by the cylinder 17 and consequeiit-ly the electromagnet 56 is energized. This energization of the elcctro-inagnet 56 as above stated, attracts the armature 5 k and places thedxerminal 52 intdengagement with the governor arm 48, while the terminal 53 is moved from engagement with the governor arm 49, the governor arm 49 being free to move and consequently permits the retraction of the "carriage and cylinder 17 to the selected position, at \vliichtime the contacts 66 due to the shouldered portion 63 of the cylinder 17 causing the separation of the contact 66, open the circuit through the .clectromagnet 56 and cause the deenergization thereof, such deenergiz ation releasing the armature 54 to the action of the spring 57, so that the terminals 52 and 53 are reversed, the terminal 52 being disengaged from, the'arm 48 whilethe terminal 53 is placed in engagement with the arm 49. This action releases the bell ringer frame 35, so that the arm 59 is moved to close the contacts 165 and 166 to thus automatically actuate the audible alarm in the called station.

Disposed near the electro-magnet 56, are

call-up circuit forming spring terminals 165-166, the upper one of which is disposed in the path of and adapted to be actuated by the arm 59, .of insulation carried vby the frame 35, and provided with the reduced end 60 and the notch 61, intermediate of its ends, the same being provided to permit the call-up terminals to be separated and the line open, when adjacent the end 6O or notch 61, and to be closed when in between;

Mounted upon the enlarged portion of and exteriorly of the cylinder 17, beyond the circumferential groove 22 thereof, are

the studs or pins 62, one to each longitudinal groove 18 of the cylinder, and formed upon the extreme inner end of the cylinder are the staggered shoulders 63, one to each pin 62 and groove 18, and each in line with its respective pin and groove. The ribs 61 formed by the series of longitudinal grooves 18 in the cylinder are provided each with a series a, of teeth, one to each'subscriber. All of the teeth are cut in circumferential alinement, said teeth forming a circuit making and breaking device to operate the respective shunting devices in the system, the co-acting spring contact terminals 65, being disposed to engage the teeth of one rib at a time, asshown in Fig. 3, and the specific purpose of which will be set forth in the operation later on. Disposed in the path of the staggered shoulders 63, of the selecting cylinder is another pair of co-acting spring terminals 66, whose purpose will appear later on. A conductor 67, through the conductor 13S, batteries 139, conductor ltO, electromagnet 56, and conductor 140 Connects one terminal of the pair of contactsother pair of terminals 68, which are disposedupon the plate 1st, and in the path to he closed and opened bythe actuation of the plate 9 of the'carriage, the purpose of which will also presently appear.

bracket 69, whose hooked lug Z0 projects downwardly and in the path to enter-between the pins 62, and insure upon the extreme inward movement of the selecting cylinder, the proper registering of the longitudiual grooves with the locking and guide screw or-pin 23, thus insuring the proper registering of v the cylinder in case Connected to the top of the vframe of the key is a the pointer did not exactly point to the proper dial number pushed the rod 24:.

The pawl P is properly carried by the frame and has its engaging end disposed to ride in one longitudinal groove .18, or engage one set or row of teeth a at a time, the spring p holding the same toward the cylinder 17 at all times. This pawl P is so when the operator disposed as to permit the cylinder 17 move ment toward initial position when in engagement with the teeth (a, but prevents the inward pushing of the cylinder. the purpose and operation of which will be set forth later on.-

SubsI-rz'bcWs lode-out and shunting (Zecice.This device, which is shown mounted in diagram iirFig. 1, and in detail in Figs. +1, 5, 0. and 8, consists primarily of the main supporting plate 71,having journaled therein and in the auxiliary plate 72, a shaft 73, which carries thereon the shunt or receiver hook lock disk 74, provided with the series of pins 7 5, which correspond in number to the grooves 18 of the selecting cylinder 17, said pins forming the operating means to control the receiver hook 117, or the shunt connections, as will presently appear. It is to be understood that although pins 7 5 are here shown, that grooves, or other projections may he used, and that there must be as many pins as there are figures on the dial of the selecting key. The pins 75 control the pawl 77,.whichis secured to the plate 71, by any well-known'means, and is provided at one end with a spring 78, which-is adapted to contactthe pins 75, to raise the pawl 77 from engagement with the notch of the receiver hook lock or shunt controller 79, which is formed in two parts or arms 30 and 81, and is secured to the plate 71 by the post 82. Secured, to the controller 79, an armature 83, said armature being provided to release the part 81 to locking position. larried by the part 80 of the controller, is a pin 84, and

a notch 85, which is adapted to receive the pawl 77, so that the controller may be locked and thus hold 'the receiver hook in shunted position.

By the rotation of the plate or disk '74, the pawl is actuated to be raised or lo'wered from engagement with the notch 85, thus when the line is free,vthe pawl is out of engagement or when the subscriber is called,.

but when two subscribers are in communication, the pawl 77 of the remaining sub- 'scribers sets is in the notch 85 of their re spective controllers and the line is dead to them, as their transmitter and receivers are shunted from the line.

Mounted through a slot 86 in the plate 71 and upon the opposite side to the controller, is a weight 87, which is connected to the free end of the part or arm 81, and which when the controller is lifted, the pawl 7'7being disengaged therefrom. and the electro-magnet 88, being energized, attractinglhc armature 83, and pulling it outwardly so that its lower end is disengaged from the weighted end of the arm or part 81, will cause the said arm 81 to fall by gravity and engage the pair of terminals 1341-135, shunting the transmitter and receiver of this set from the loop circult, and at the same time opening the line there, thus providing a means should a receiver be taken OH or be oif at that instant, that the exchange may select the called subscriber and place the calling subscriber into proper line connection, shunting the subscriber whose receiver is off the hook. The main shaft 7 3 also carries two ratchet wheels 90 and 91, respectively. one of whichis an actuating ratchet and the other of which is a retrograde movement preventing ratchet,

and disposed to operate upon these ratchets to impart to the shaft73 and the disk 74 the proper rotation, is the bell-crank lever pawl 92, which is pivoted to the arm 72' of the auxiliary plate 72, and has pivoted to its upper free end the pawl 93, the pawl 93 operating to rotate the shaft and disk, while the pawl 92, operates to prevent its moving too far or retrograding. In order to prevent theretrograde movement of the shaft 73 when the pawl 93 has been partially moved to grip a new tooth of the ratchet wheel, the member 92 being not yet engaged with said ratchet wheel, a spring 73 is provided, as clearly shown in Figs. 1, 5 and 8, said spring 73 being disposed to engage the ratchet wheel and at the same time act as a slight retarding means to prevent the overrunmng action of the shaft 73 in the desired direction. In order to operate these two pawls simultaneously to operate the shaft, an armature 94, is connected to the end of the pawl 92 at its connection with the pawl 93,

so that the energizing of the eleetro-magnet 95, will pull upon thepawl 93 and cause the pawl 92 to be pushed and lifted, the pawl 93 engaging the ratchet 90 to rotate the shaft, and the pawl 92 engaging the ratchet 91 to prevent the shaft moving too far or retrogl-ading, a spring 96 being employed to return the pawls upon the deiinergization of the electro-magnet 95. By making and breaking the contacts 65-65' by the teeth (1 upon the" selecting cylinder, the electro-lnagnets 101 and 95 are energized as will later appear, and the shaft 73 and disk 74, are operated in synchronism or in step witlnthe movement of the teeth a, and thus the selected subscriber is permitted a line connection, and the remaining receivers and transmitters are shunted from the line, and are dead.

The electro-magnet 95 is energized by a storage battery B while the clectro-magnet 101 is energized by the main transmission battery 111, but as herein shown, the electromagnet 95 is controlled through the contacts 129 and 130, controlled by the main electromagnet or relay 101, disposed upon the rear of the plate 71, and connected in the talking circuit, the energizing of the electro-magnet to energize the electro-magnet 95 and operate the shunting and lock-out mechanism.

The shaft 73 further carries a disk 102,

having a set ofperipheral pins 103, here shown three in number, and a( set of outwardly projecting facial pins 104:, which are six in number and are disposed intermediate of the respective'peripheral pins 103. The pins 103, are employed to operateth-e circuit containing theelectromagnet 88 through the spring terminal contacts 105, while the pins 104 are adapted to engage and operate the spring terminal contacts 106 which are in circuit with the call-up alarm 200. The contacts 105 provide an auxiliary means for energizing the electro-magnet 88, to release the arm 81, to produce a shunt and open the local battery circuit, should the subscriber neglect to hang up his receiver after his conversation is ended.

In order to provide a visual signal v or indicator to advise the subscriber that the line is free or busy, there is mounted upon the extreme end of the shaft 73 and in view of the subscriber a signal disk 107, which is provided with three series of two colored portions 108 and 109, as shown in Figs. 4 and 5, a red color indicating busy and a white. free. By this means, the subscriber may be notified when he may expect to get the exchange for communication, or even in the event that he should have taken there suppose that the calling-subscriber has requested the exchange operator for telephone #5. The operator now rotates the push rod 24 to the left, operating the pawl and ratchet clutch so that the selecting cylinder is rotated, and when the dial indicates #5, the rod 24 is ready to bepushed upon. The push rod 24 is now pushed upon carrying with it the carriage and selecting cylinder and also the ringer frame 35, the electromagnet 56 now being energized due to the closure of the spring66 by the carriage, the

armature is attracted against the spring 57 so that the terminal 52 is placed move the governor arm 18, and the frame 35 is locked. Upon the release of therod 24, however, the spring 3', returm't the carriage and cylinder to' selected --pnsition, at which point the springs 66 are released and the electro magnet 56 is deenergiz'ed, its arma ture being released to the spring 57. The terminal 52 is now disengaged from the governor arm 48, while the terminal 53 is placed in engagement with the governor ar as, thus freeing the gears 11 and '33 against movement an consequently holding the cylinder and carriage' at selected position. During the movement. of the carriage and cylinder, that is when the electro magnet 56 is energized, and

contacts 65, and thus energize the respective electromagnets 101-and 95 so that the shafts 78 in all of the subscribers sets are rotated, the carriage and selecting cylinder being halted when the staggered portion'or the proper shoulder-63 has permitted the terminals 66 to separate, at which time the circuit including batteries 1391, terminals 66 and electro magnet 56 is broken, and the electromagnet 56 is denergized, permitting the spring 57 to pull the terminal 52 out of before its deenergization, the teeth a, and the "contacts ode-f are-2 brought into play.

This action causes the teeth a, to actuate they-4 engagement with the, governor arm 48, and

engaging the terminal 53 with the governor arm 49, so that the frame 35 is actuated by itsspring and is moved to the opposite end of the main frame ringing the call-up alarm" Should" 200 in the selected subscriber set. the selected subscriber not, reply at once, the

exchange operates the auxiliary push rod: 38'

any well known call-up mechanism. By

this means it will be seen that the entire selecting operation is controlled by the exchange operator, and that the carriage and selecting cylinder will remain in this selected position, as shown in .Fig. 3, and cannot be changed by the operator by the manipulapawlP and its retaining spring 7), which is carried by the frame and dispos d to engage the teeth a of the cylinder as will presently appear,.-either 'by pushing or rotating, as

the selecting cylinder is locked against fur ther inward movement by means of the pawl P-and against ,furtherrotation by means of the pin 23. The only way it can possibly be changed is by the removal of the jack plug J, at which time the electromagnet 56 is energized, and the carriage governor arm 19 is released to permit the carriage and selecting cylinder to return to initial position, Fig. 2. Should the subscribers impose upon the exchange, this action'may be taken, but as central can hear the conversation, and therefore knows when it is completed, the jack plug J is removed, and the various othersubscribers are placed in line connection, the recession of the car riage and cylinder automatically operating the terminal contacts 65, to actuate the lockout and shunting devices throughout the system placing all stations in condition to tion of the push rod 24, due to the locking obtain the exchange, and operating the visual indicators to indicate such condition.

When the carriage and selecting cylinder are first pushed in the teeth a are not in line with the contact terminals 65, but as the pins 62 upon thecircumferenceof the selecting cylinder are engaged by the guide hook '70, depending from the main frame, the se- .lect-ing cylinder is given a slight turn, so

that the indicator would point half way between the number selected and the next succeeding one, that is if #5-is selected the indicator would point half way between #5 and #6, thus placing the teeth a in line with the terminal contacts 65, and the locking pawl P so that anyrecessionof the cylinder will actuate the contacts 65 to Operate in synchronism the various 1ock-out and shunting devices in the system to be halted when the proper set is in line connection and ready I to be called up.

The selecting cylinder, when ready to be pushed in, has a space between two rows of teeth a disposed to aline with the lower end of the pin 23, said pin being of considerably less width than the space, while the spring actuated pawl P, which is of substantially the same width as the space is also disposed in line with a space between two rows' of teeth a. Thus when the cylinder is pushed in, the. cylinder will be properly guided by the pawl P and when at the end of the stroke and the in 62 is engaged by the hook 70, the cylinder will have a slight rotation imparted thereto, such slight rotation placing a row of teeth a in line to engage the pawl P but not sufliciently far to move the space out of alinementwith the'p'in 23, thus the pawl P will lock the cylinder against a further pushing movement, while the arm 53 will lock the arm 49 due to the spring. 5? s0 that the cylinder is locked against retraction.

Thus the operator cannot by mistake change the talking circuit by attempting. to move the selector through the movement of the push rod 2450 that any other, but the set The selector cannot therefore, be readjusted by the exchange, either by mistake or wilfully, until "the "jack plug J is removed, and the carriage and selecting cylinder are returned to initial position. As soon as the conversation is through, or central operator chooses to take possession of the line, the jack pin J, is removed, thus completing the circuit-through conductors 67 and 13S, batteries 139, conductor 1 10, electro magnet 56, and conductor 140 to the spring contacts (36, the electro-magnet 56 being energized to release the carriage and selecting cylinder release escapement, bringing all instruments to line connected position, and the selecting instrument to initial or zero position.

In order that the various circuits may be traced in the diagram, as illustrated in Fig. 1, to demonstrate the full operation of the present system, although it is to be un- 4 derstood that other formsof circuits may be employed with the present selecting key and lock-out device, the circuits will be traced in rotation or in their correct order, beginning with the calling of the operator or the exchange and the answering of such call by the operator, and to the final restoration of the various subscribers instruments to the line. With the various instruments in the position as illustrated in Fig. 1, the contacts 65-435" are closed so that the signal S is connected to the line conductors L-L through the respective conductors 170, 171 and 172, so. that all subscribers sets are in line calling connection with the exchange E. Thus the ine will be connected so that the exchange can be called by any one of the subscribers sets.

Pie-supposing that a subscriber desires to call the exchange, the receiver R is removed from the hook 117, and the magneto M at the calling subscribcrs set is actuated to actuate the exchange signal S to indicate to the exchange operator that the calling subscriber desires to be connected with a selected subscriber. Should the magneto M be dispensed with, the. local battery B of .the calling subscribers set will be connected to the line through the receiver hook 117 andcontacts 120 and 121, thus bringing into that line the transmitter T and the receiver R with the local batteries B, which will phergize, in short lines, the signal S, and give such indication to the exchange. The circuit closed when the receiver hook 117 is raised, is as follows: The contact point 121, the conductor 122, the coil 123, conductor .124, transmitter T, conductor 125, batteries B, conductors 12(i--12l3, the contacts 167-168, the conductor 126, the contact 120, and the receiver hook 117. Assuming that the calling subscriber desires to converse with a subscriber, as for instance No'. 5, exchange operator now inserts the jack plug J in the calling subscriber socket 2, this action opening contacts 2'2. "The push rod 2-4 of the selecting key K is now rotated until the indicator indicates N o. 5, at which time the push rod is pushed upon and during such action the contacts 66, due

to the engagement thereof with the enlarged portion oi the cylinder 17, are closed and before the release of the key actuating rod 24, a circuit is closed at (36 and includes one contact 66, the-conductors G7 and 138, the battery 13!), the conductor 14-0, the electromagnetfifi, the conductor 140 and the ot her contact 66. Thus the clectromagnet 56 is energizer! and attracts the armature 51 to place the arm 52 above and in engagemen with the arm 48 to lock the automatic ringer frame 35 against release. At the same time contacts 22 of the jack 2 are held open? by'the jack plug, the electromagnet 56, as

will later appear is not affected now by the contacts 68.

As before stated, previous to" the cylinder, 17 having reached its full limit of movement, the hook 70 engages the pin 62, and thus rotates the cylinder 17 to bring a single row of teeth a in line with the pawl 'P, and the pawl due to its spring 79 locks the cylinder against further inward movement and permits the same to retract to the selected tooth of the row a, while at the opposite side of the cylinder another row of teeth a are disposed to engage the contact 65 and thus close the talking circuit and intermittently open and close another circuit, as will pres-' ently appear. W hen the contact 65 is in the depression between the respective teeth a,

- the closure is made between the contact 65 and terminal 65", while when the contact 65 is riding upon one tooth a, the contact is open at 65 and closed at 65, thus intermittently and alternately forming a talking connection and connecting the batteries 111 to the line.

The release of the push rod 24, due to the spring 3 moves the cylinder 17 and frame9 Y toward the initial position, and asthe contacts 66 are closed by the enlarged portion of the cylinder 17, the circuit controlling the electromagnet is energized until the opening of said contacts 66 due to the snapping of said contacts from one of the staggered.

portions 63 of the cylinder 17. The opening of the circuit thus described, permits the spring 57 to hold the arm 53 above the arm 49. and thus lock the arm 19 to hold the cylinder 17 and carriage 7 locked against further movement toward initial position. As

the cylinder 17 .was moved toward initial position and before being stopped by the arm 53, the teeth a engaging the contact 65,

- operated synchronously, to lock out all uncalled sets and place into line connection the single called set.

The circuitclosed to lock out the uncalled sets and-connect the line in the called set, is as follows: The contacts 65'--,65', the com ductor 110, the battery 111, the conductor '112, the line conductor L, the receiver hook 117, the contact 118, the conductor 115, the conductor 114:, the two closed contacts 106106, the conductor 113, through the portion of the line L, as indicated in Fig. l, of. the substations, the conductor-128, the

- not be affected as the bell 200 is electromagnet 101, the conductor 128, and the line L, thus intermittently energizing the electromagnet101 in all substations. Theenergization of eachelectromagnet 101 operates the armature 101 in each set and thus causes the contacts 129130 to .'intermittently close a circuit including the electrothe contacts 129 130, the conductor 131, the

electromagnet 95, the conductor 132, the bat teries B, and the conductor 133. Thus the intermittent energization of the electromagnet 95 in each set will operate the armature 94: to step the shaft 73 and the disk 102. The disk 103 in the uncalled set will be moved to indicate red if the line is busy. At this stage in each uncalledset, the receiver hook is lockedand the uncalled sets shuntedfrom the line, by reason of the lever being locked in down position by the lock 77, engaging the notch 85. At the same time, the contacts 134.'135 are closed by the lever 80 in such position as to shunt the uncalled sets from the lines L.L through the conductor 136, contacts134-135 and conductor-137. As the uncalled sets receiver hooks are thus locked, it is impossible for the sameto be released by lifting the receiver, and the conductor 136, thecontacts 134c135 and the conductor 137 completes a shunt around thesubstation. The substation is thus shunted from the line. Also as the pin 104; in the uncalled set, is out of con tact with the contacts 106, the bell*2 00 in each uncalled set is held inoperative and will actuated in the called set; When the cylinder 17 was stopped in itsmovement, due to the contacts 66 being opened by slipping from engagement with the shoulder 63, the electromagnet 56 was deenerglzed and permitted-the spring 57 to move and hold the armature 51. At this time, the arm 52 releases the arm 48, to the action of the spring, and the spring 14: moves the call-up alarm frame 35 to initial position, so that the contacts 165166 controlled by the arm 59 of insulation are held open, due to the positioning of the end of the contact 165 in the recess 61fof the bar 59. Thus the-movement of the frame 35 the bar 59 to ride over and press the contact 165 to engage. the contact 166 and thus throwinto the line the call up machine M of thesystem. By this means the call up machine, which may be operated at all times, ,or when desired, is thrown into the line through the'wires wy 'to energize the call up alarm:200 in the called set. The period of such ringing of the call alarm 200 depends upon the length of the bar59 and 166- Should the-contact 165 be raised and sepaand the bar 59, will cause the lower edge of I until its curved end 61 passes over the conator'atthe exchange removes the jack plug rate from the contact 166, the call up mathe call up machine M when .contacts' 165 166 are closed, is as foll0ws:'The ground 9, the conductor a, the machine M, the conductor w, the contacts 166-165, the conductor c, the conductorj, ofjack plug J, the socket 2, the line L, the receiver hook 117 in the called set, the contact 118, the conductor 115, the call-up alarm 200, the conductor 114, the contacts 106 which are closed by the pin 104 in the called set, the conductor 113 and the ground g".

As the locking lever 77 in the called subscribers set is raised so as not to be in the path to engage the notch 85 of the arm 80. the receiver hook of the called subscribers set, when the receiver has been removed therefrom, will automatically riseand thus open the contacts at 117-118 and bridge the contacts 120 and 121 and thus throw into the line the local battery circuit of the called subscribers set so that the called subscriber and the calling subscribers sets will be placed into connection with the line wires L and L.

At the end of the conversation, the oper- J, and permits the contacts 2-2 toclose and as the contacts 68 are closed, due to the frame 9 of the selecting key, engaging them, the circuit including the electromagnet is closed, and thus the armature 51 is moved in opposition to the spring 57 to remove the arm 53 from engagement with the arm 49.

. This action will release the carriage 7 and move the cylinder 17 under the action of the spring 3", so that the cylinder is moved, as for instance from the position shown in Fig. 3t0 that shown in Fig. 2. During this movement, the teeth a are in engagement with the contact and will intermittently open and close the contacts 65" and 65 and thus throw into line the battery 111, which as before described will actuate all of the electromagnets 101 in every sub.- scribers set to automatically operate the shafts 73, the electromagnets 95 and armatures94, so that the disks 102 Wlll be placed in normal position to indicate that the line is free and that the exchange can be called by all subscribers. At this time all of the hooks 117 can be raised, as the locking lever 77 is in raised position and out of the path to engage the notch 85 of the Various arms 80.

In the event that a receiver in any set is .left 011' of the" hook 117, such hook is consequently raised, to permit contacts 134- 135 to be opened, w1th contacts l67168 closed, and the arm 80 dueto the armature catch 83 will have carried with it the arm- 81. Now as the shafts 73 are rotated, as

before described, during the selection of a called subscriber and the locking out of the uncalled subscriber, the pin 103 carried by, the disk 102 will engage the contacts 105 in each set, thus closing a circuit in each set to energizethe electroma net 88. Thus in the set where the hook 117 is raised, the armature catch 83 will be moved to the position as shown in Fig. 5, and should this be an uncalled set, this set will be shunt.- ed from the line by the closure of the contacts 134-435 and opening of the contacts 167-468, due to the falling thereupon of the arm 81. This circuit is as follows: The contacts 105, conductor 151, electromagnet 88, conductor 150, battery 149, and conductor 148, thus energizing the electromagnet 88 to attract the armature catch 83, as above described, to release the arm 81, which due to gravity will fall and close the contacts 134 and 135, thus shunting the set from the lines L-L.

As before stated, the contacts 167-168 are held opened by the arm 81 when down,

and by this arrangement it is evident that the.local battery B is saved should the receiver R, be purposely or accidentally left off the hook 117.

The circuit traced through the calling substation to the exchange is as follows :-Assuming the selecting key at the exchange to be at zero position, and therefore the shunts at 134-135 at each sub-station open,and thus all sub-stations connected to the line for calling the exchange, and that a substation desires to call the exchange, the magneto M is operated and the signal S, at the exchange is energized, asis the usual practice, and the exchange operator upon not-icing tl1e signal will insert the answering jack plug. The calling subscriber now removes the receiver It from the hook 117, so that the hook rises and bridges contacts 120-121.

The circuit with the exchange and the calling sub-station is as follows :The answering jack socket 1, closed by the answering jack plug, at the exchange, the line L,- the hook 117 of the calling sub-station, the

conductor 122, the coil 123, the conductor 175, the receiver cord R, the receiver R, the conductor R the portion of line L, to which the conductor R connects, the conductor 128, the coil 10.1, the conductor 128', and the line L, to the exchange. Thus the receiver R is connected to the line, so that the-exchange operator can ask the sub-station the desired party to which the calling substation desires connection. Simultaneens-l with the removal of the receiver R from the hook 117 in the calling sub-station, the transmitter T in such sub-station is connected for transmitting to the line as follows:The socket 1, the line L, the hook 117, the contacts 120121,tl1e conductor 122, the coil 123, the conductor 124, the transmitter T, the conductor 125, the battery B, the conductor 126, the conductor 126, the closed contacts 1ti71(38,the conductor 126 back to the contact 120, the hook 117, the portion of the line L, the conductor 128, the coil 101, the conductor 128, and the line L to the socket 1 at the exchange. The exchange'andcallingsub-station are now properly connected and the exchange, whlle 'the calling subscriber holds the receiver off the hook 117.

and is placed in communication by the exchange operator, who manipulates the selecting key before described, will be placed in communication with the called substation.

The manipulation of the selecting key operates the lock out devices in the uncalled sub-station so that the receiver hooks are locked and the shunt connections at the uncalled sub-stations are closed, thus shunting {he complete uncalled sub-stations from the The circuit for energizing the various lock out devices in the different sub-stations, even including the called sub-station are as fol lows: The contacts (S5 -,the conductor 110, the battery 111, the conductor 112, the line conductor L, the conductor 128, in all substations, the electromagnets 101, the conductor 128' and the line L, this circuit energizing .all electromagnets v101 which in turn being energized attracts their respective armatures 101, and close the contacts t2$)-13O in each sub-station to intermittently close and open a circuit including the electromagnets 95. I'Ihe circuit tothe electroma net 95 is as follows and includes the contacts 129 130, the conductor 131, the-electromagnet- 95, the conductor 132, the battery B, and the conductor 133.

The energization of the electromagnet 95 in the tin-called sub-station causes the disk 74 to cause the lock 85 to engage the arm 80 and thus lockthe arm so that should .the receiver be lifted from the hook in such un-" called sub-stations, the arm 8O-cannotv be raised and being held in its downward position effects the closure of contacts 134-135 and consequently the shunt connection in thus placing the various lock-out devices under the absolute control of the exchange operator so that when the calling and called talking circuit, a selecting instrument at theexchange, and a shunt operating device in each subscribers instrument influenced only by the selecting instrument to shunt the uncalled subscribers instruments from the talking circuit and atthe same time open all the transmitter circuits to thebatteries in the instruments so shunted.

2. In a system of selective telephony, the combination of an exchange and. a plurality of sets of subscribers instruments connected for the transmission of intelligence, said exchange having manually operated means for selecting a subscribers set and shunting the uncalled sets, and automatically operated means for signaling the called set, said selecting means being the sole instrumentality for selecting and signaling a called set, an for shunting the uncalled sets.

3. In a system of selective telephony, the g5 combination-of an exchange and a plurality of sets of subscribers instruments connected for the transmission of intelligence, said exchange having means for selecting the desired set, signaling the same, and shunting all uncalled sets from the system, said selecting means being the sole instrumentality for 1 selecting and signaling a called set, for

shunting the uncalled sets, and for connecting all sets to the line for communlcation' with the exchange. 4. In ,a system of selective telephony, the

combination of an exchange. and a plurality the remaining sets to isolate them from the line, and for automatically operating the call-up device of the set called, and auxiliary'means mounted in said mechanism for repeating the signal.

V 5. In a system of selective telephony, the combination of an exchange-and. a plurality of subscribers sets of'instruments, including a transmitter, a receiver, a call up alarm,-a shunting device and a visual indicator, said exchange and subscriberssets of instruments being in electrical communication, and mechanism mounted at the exchange and manually operated to connect any two of the subscribers sets of instruments for communication, to operate the shunting devices and visual indicators in the remaining sets of instruments, and for automatically operating the call-up alarm of the set selected.

6. In a system of selective telephony, the combination of an exchange and a plurality of subscribers sets of instruments, including each a shunting device, a visual indicator, a transmitter, a receiver and a call-up device, said exchange and subscribers sets of instruments being in electrical communication, and a selecting device at the exchange for selecting any one set for connection with a calling set, said device automatically operating the call-up device in the selected set,

giving a visual indication in all sets, and shunting all sets except the called and calling set. A

7. In a telephone system, the combination with an exchange station having a selecting apparatus, of a series of subscribers sets of instruments connected with the exchange station for the transmission of intelligence, each having a local battery circuit, a shunting device controlled from the exchange through the selecting apparatus, and a visual signal operable by said shunting device to indicate the condition of the local battery circuit relatively to the transmitting circuit.

8. In a selective system of telephony, the combination of an exchange and a plurality of sets of subscribers instruments connected electrically for the transmission of intelligence, a manuallyoperated selecting device in the exchange and connected in the line, a receiver hook lock in each subscribers set, means controlled by the selecting device to cause said lock to be engaged. or freed, and a shunting connection with the line at each subscribers set controlled by said lock, whereby when two sets are connected for communication all of the other receiver hooks are locked and the sets are shunted from the line.

9. In a selective system of telephony, the,

combination of an exchange and a plurality of sets of subscribers instruments connected electrically for the transmission of intelligence, a manually operated selecting device in the exchange and connected in the line, a

tuatin communication, all of the other receiver hooks are locked and the sets are ahunted from the line, and a signal device controlled 1 by each lock controlling means to indicate the line condition of its respective subscribers set.

10: In a selective system of telephony, the combination of an exchange, and a plurality of sets of subscribers instruments connected electrically for the transmission of intelligence, a manually operated selecting device in the exchange and connected in the line, a receiver hook lock in each subscribers set, means controlled by the selecting device to cause said lock to be engaged or freed, and a shunting connection with the line at each subscribers set controlled by said lock, whereby when two sets are connected for communication all of the other sets are shunted from the line. i

11. In a selective system of telephony, the combination of an exchange, and a plurality of sets of subscribers instruments connected electrically for the transmission of intelligence, a manually operated selecting device in the exchange and connected in the line, 2|. receiver hook lock in each subscribers set, means controlled by the selecting device to cause said lock to be engaged or freed, a shunting connection withthe line-at each subscribers set controlled by said lock, whereby when two sets are connected for communication -all of the other sets are shunted from the line, and a signal device controlled by each lock controlling means to indicate the line condition of its respective subscribers set.

12. A selective system of telephony, having an exchange, and a plurality of subscribers sets of instruments connected electrically for the transmission of intelligence,

a selecting device at the exchange, a lock out device in each subscribers set influenced by theselecting device, a shunt connection with the line at each subscribers set actuated by the lock out device, and a signal device in each subscribers set, the placing into communication of two subscribers sets, ac all signal devices to indicate their condition relativel to the line while the shunt connections in all other sets than the 1 calling and called sets are closed and the instruments shunted from the line.

In testimony that I claim the fore oing as my own, I have hereto afiixed my signature in the presence of two witnesses.

' RUBEN C. M. HASTINGS. Witnesses:

L. A. KAAIis,

E. C. WOODWORIH.

Copies of this patent may be obtained for 'flve cents each, by addressing the Commissioner of Patents,

Washington, I). 0. 

